The present invention relates to electric lines for connecting points between which heat transfers have to be controlled and limited, particularly between a hot source and a cold source. There are two obvious, but non-limitative fields of application, namely cryogenics and space.
At present, stainless steel cables are widely used for this purpose, but suffer from the disadvantage of being voluminuous and having a high weight, as well as a relatively high electrical resistance. Finally, they do not make it possible to modify in the desired manner the temperature along the cable.
Consideration has also been given to a different design consisting of depositing copper layers on an insulating and generally flexible support, which can also be locally or completely rigid. These layers are interrupted at the points where it is wished to have a good thermal insulation and they are connected by manganin wires welded to the tracks and fixed by a random process to the insulating support. Copper has the advantage of a low electrical resistance, whereas manganin connections, manganin being a material with a high thermal resistance, constitute barriers to heat exchangers along the connections. However, the laying of manganin wires cannot be laid in a sufficiently reliable manner to provide a completely satisfactory solution.
Thus, the present invention provides an improvement in the design of these flat cables by simpler and more reliable manufacture, as well as providing the possibility of modifying the electrical and thermal resistance characteristics along lines of such cables.